[Zenfone 2 Laser Q&A, Help & Troubleshooting] HampTheToker:
So, here's my (hopefully) brief write-up to acquire root, install recovery, make a backup, and ,optionally, install the Xposed framework. Before getting started be sure to have plugged your phone into your computer for Windows to download and install drivers for your ZF2L. Also, you will need to download and install adb in order to use command prompt to flash files to your phone. This link will take you to a thread here at XDA for Minimal ADB and Fastboot. This is the easiest way to install and use adb and fastboot on your computer. Once you have it installed you can proceed to the next steps.

First, you'll need to unlock your bootloader using the app found here. It's in a .zip files for whatever reason, so you'll need to use 7zip or WinZip or WinRAR or something on your computer to extract it and install to your phone. You can plug your phone in and place the extracted app on your external or internal storage or use a cloud storage app like Dropbox or Google Drive to transfer it to your phone. If you plug it in and place on your internal or external storage, then you'll need to use File Manager (it's a stock app) to find and install it. Once installed just run the app. It's extremely user friendly and straightforward. Your phone will reboot when it's done.

Next, you'll have to temporarily boot a modified boot.img using Minimal adb and fastboot. Once this step is completed and the phone boots up you'll need to go to the Play Store and install Supersu as well as Busybox if you want your root apps to work properly.

Go here on your computer and download the modified boot.img named boot_200007.img and place it in the Minimal adb and fastboot folder. As you can see in this screenshot:

my adb and fastboot folder is located at C:\Windows\Minimal ADB and Fastboot. Once you have the boot.img copied to the right folder go ahead and connect your phone, if it isn't already. Hold the power button and restart the phone. As soon as the screen goes off hold the volume up button until the phone boots into fastboot mode. If you have trouble with this, you can just turn the phone off, and then press and hold power and volume up until it boots into fastboot mode. Right click the Minimal adb and fastboot icon and select run as administrator. As long as it's installed correctly, the following commands shouldn't give you any error messages. Before we go further, let me briefly explain what we're doing at this point. We have two options: we can flash the boot.img which will physically write it to the proper partition on your phone, or we can simply boot the phone while the modified boot.img remains on your computer and unwritten to the phone, which is what we want to do in this case. To do this we enter the following command:

fastboot boot boot_200007.img

Your phone should reboot on it's own and once it does open the app drawer and check to see if Supersu is installed. If it isn't, open Play and install it, as well as Busybox. Open Supersu and make sure you have root. Once your done, open Busybox and install Busybox to /system/xbin and reboot when finished. At this point, you can disconnect your phone and ensure the Supersu does give you any errors. Test it by installing your favorite root apps, and since you're new to root, I'll give you some suggestions. You can do a google search to find Adaway. It isn't available in the Play Store because it's an adblocker and ads are Google's bread and butter, but it sure is nice to use apps without intrusive apps trying to sell you something no matter where you go. Root + Adaway have been solving that problem for years. Next we have Root Explorer which is my root file manager of choice. Another community favorite is ES File Manager. Both are great. Titanium Backup, Flashify (install it for the next step), and Viper4Android (not in Play search XDA) are all must have apps for root users. Install and open some of those (especially Flashify) just to verify that they work and let's move on the next step.

Download TWRP here and place it on either internal or external storage. Open Flashify and select Recovery Image and then find and select recovery551_200431.img. This will write the TeamWinRecoveryProject custom recovery to the recovery partition of your phone which will allow you to view, backup, restore, and modify all the relevant partitions that make up the Android operation system. At this moment, it's important to understand that you are now more than capable of completely and totally bricking your phone...but you're also capable of recovering from most problems that can arise from flashing mods and using root apps. This is where we'll make a complete backup for just that very reason.

After you've flashed TWRP using Flashify, you'll be prompted to reboot. Do so, and your phone will reboot into recovery. You'll see a message one the first run with a check box to disable modifications to system or something along those lines (can't remember exactly what it says lol), just don't check it. Leave the box uncheck and swipe the bar to allow modifications to system. Now, you should see the main menu. Select Backup and make sure that Boot, System, Data, and Cache are selected and rename the backup to something along the lines of "stock_rooted" or "stock_backup" if you wish and you're ready to create a nandroid backup. Swipe the button and give it a few minutes. Once done, just reboot and you're good to go.

Now to install Xposed, you'll first need to install the Xposed Installer .apk on your phone from here. To flash Xposed, reboot into recovery (turn off then hold power + volume down) and select Install then select the Xposed .zip package xposed-v80-sdk21-arm64.zip that you downloaded and placed on your internal (preferrably) or external storage beforehand. Once finished just reboot and you're done. Be warned that the first boot after installing Xposed will take a long time (approx. 5-10 minutes). Greenify, Gravitybox (LL), Youtube Adaway, Flat Style Bar Indicators, MaxLock, and NotifyClean are just a few of my favorite Xposed modules. Be sure to read the descriptions for these modules carefully and do not forget that Xposed modules can be tricky and cause problems if they're not compatible with your phone. Honestly, you should ask here before installing any modules that I haven't already mentioned.

Anyway, that's my brief write-up lol. Hopefully, that isn't too hard to follow. Don't hesitate to reply back if you encounter a problem, have any questions, or simply want to report your success and ask for tips. I'll leave you with this little tip: don't give up on ZenUI. It definitely doesn't hold a flame to stock Android, but if you use a third party launcher like Nova Launcher and use Developer Options to increase animation speed to .5 seconds (or turn them off entirely) it's really not so horrible, in my opinion. It's damn sure not TouchWiz.